Multi-TFM approvals (#675)

Author: sungam3r

.github/labeler.yml

@@ -1,5 +1,4 @@
-test:
-  - tests/**/*
+test: ['tests/**/*', '!tests/ApiApprovalTests/**/*.txt']
 
 CI:
   - .github/workflows/**/*

tests/ApiApprovalTests/ApiApprovalTests.cs

@@ -1,4 +1,10 @@
 using System;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using System.Runtime.ExceptionServices;
+using System.Xml.Linq;
 using PublicApiGenerator;
 using Shouldly;
 using Xunit;
@@ -22,17 +28,57 @@ public class ApiApprovalTests
         [InlineData(typeof(Server.Transports.WebSockets.WebSocketTransport))]
         public void public_api_should_not_change_unintentionally(Type type)
         {
-            string publicApi = type.Assembly.GeneratePublicApi(new ApiGeneratorOptions
+            string baseDir = AppDomain.CurrentDomain.BaseDirectory;
+            string projectName = type.Assembly.GetName().Name!;
+            string projectFolderName = projectName["GraphQL.Server.".Length..];
+            string projectDir = Path.Combine(baseDir, $"..{Path.DirectorySeparatorChar}..{Path.DirectorySeparatorChar}..{Path.DirectorySeparatorChar}..{Path.DirectorySeparatorChar}..", "src");
+            string buildDir = Path.Combine(projectDir, projectFolderName, "bin", "Debug");
+            Debug.Assert(Directory.Exists(buildDir), $"Directory '{buildDir}' doesn't exist");
+            string csProject = Path.Combine(projectDir, projectFolderName, projectFolderName + ".csproj");
+            var project = XDocument.Load(csProject);
+            string[] tfms = project.Descendants("TargetFrameworks").Union(project.Descendants("TargetFramework")).First().Value.Split(";", StringSplitOptions.RemoveEmptyEntries);
+
+            // There may be old stuff from earlier builds like net45, netcoreapp3.0, etc. so filter it out
+            string[] actualTfmDirs = Directory.GetDirectories(buildDir).Where(dir => tfms.Any(tfm => dir.EndsWith(tfm))).ToArray();
+            Debug.Assert(actualTfmDirs.Length > 0, $"Directory '{buildDir}' doesn't contain subdirectories matching {string.Join(";", tfms)}");
+
+            (string tfm, string content)[] publicApi = actualTfmDirs.Select(tfmDir => (new DirectoryInfo(tfmDir).Name.Replace(".", ""), Assembly.LoadFile(Path.Combine(tfmDir, projectName + ".dll")).GeneratePublicApi(new ApiGeneratorOptions
             {
                 IncludeAssemblyAttributes = false,
-                WhitelistedNamespacePrefixes = new[] { "Microsoft." }
-            });
+                WhitelistedNamespacePrefixes = new[] { "Microsoft." },
+                ExcludeAttributes = new[] { "System.Diagnostics.DebuggerDisplayAttribute", "System.Diagnostics.CodeAnalysis.AllowNullAttribute" }
+            }))).ToArray();
 
             // See: https://shouldly.readthedocs.io/en/latest/assertions/shouldMatchApproved.html
             // Note: If the AssemblyName.approved.txt file doesn't match the latest publicApi value,
             // this call will try to launch a diff tool to help you out but that can fail on
             // your machine if a diff tool isn't configured/setup.
-            publicApi.ShouldMatchApproved(options => options.WithFilenameGenerator((testMethodInfo, discriminator, fileType, fileExtension) => $"{type.Assembly.GetName().Name}.{fileType}.{fileExtension}"));
+            if (publicApi.DistinctBy(item => item.content).Count() == 1)
+            {
+                publicApi[0].content.ShouldMatchApproved(options => options.NoDiff().WithFilenameGenerator((testMethodInfo, discriminator, fileType, fileExtension) => $"{type.Assembly.GetName().Name}.{fileType}.{fileExtension}"));
+            }
+            else
+            {
+                // https://github.com/graphql-dotnet/server/pull/675#issuecomment-1001283947
+                ExceptionDispatchInfo? error = null;
+
+                var uniqueApi = publicApi.ToLookup(item => item.content);
+                foreach (var item in uniqueApi)
+                {
+                    try
+                    {
+                        item.Key.ShouldMatchApproved(options => options.SubFolder(string.Join("+", item.Select(x => x.tfm).OrderBy(x => x))).NoDiff().WithFilenameGenerator((testMethodInfo, discriminator, fileType, fileExtension) => $"{type.Assembly.GetName().Name}.{fileType}.{fileExtension}"));
+                    }
+                    catch (Exception ex)
+                    {
+                        error = ExceptionDispatchInfo.Capture(ex);
+                    }
+                }
+
+                // It's OK to throw any exception occurred.
+                if (error != null)
+                    error.Throw();
+            }
         }
     }
 }

tests/ApiApprovalTests/ApiApprovalTests.csproj

@@ -3,6 +3,7 @@
 
   <PropertyGroup>
     <TargetFramework>net6</TargetFramework>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>